... delivery 1 Radial needle roller and cage assemblies 2NA, NKI-type needle roller bearings 3.RNA, NK needle roller bearings without ... (roller diameter D ≤ 5mm, L / D ≥ 2.5, L is the length of the roller), therefore radially compact structure, the inner diameter ... shell hole as bearing directly within the outer rolling surface, in order to ensure the load capacity and operation the same ...